I personally own an Apple iBook and an older HP model consumer notebook.
The HP is ok build quality wise, but could be better for the weight. I held it by the corner too much and it formed a small crack over time. The iBook is more durable. I can hold it by 1 corner and there is less flex. I don't know that I would put it in a backpack full of books as people say though, press the back of the LCD and I see ripples, contrary to what I heard before I bought it.
Both are solid hardware quality wise overall. I regret not getting a faster HDD for my HP though, as it only has a 4200rpm drive. Kinda slow now.
For Apple, the Mac OS takes getting used to if you know Windows.
My HP does have a touchpad problem, some times it will randomly stop working, then lag for a bit before it works again. A known problem for my model.
I would buy another HP and Apple notebook if I buy any more.
If Dell notebooks now are anything like their desktops, in no way is Dell the same as an Apple.